S. Mahunka szerk.: Folia Entomologica Hungarica 44/1. (Budapest, 1983)

laboratory specimen are slightly larger than in field ones excepting width of the body (character No. 3) which was more variable in field population (CV = 22.9%). Variability of measurement of cuticular structures on hysterosomal plates was also comparable between the populations and sexes, however, in females it covers much broader range than in males. Especially variable is character No. 63 (the length of anterior part of posteromedian apodeme) which shows CV = 32.2%. This is due probably to the fact that this apodeme is weakly developed and becomes •completly invisible in some specimens (Fig. 6). It was surprising, however, that lengths of setae show CV s not markedly greater than other characters despite the fact that these flexible structures can hardly be measured as accuratelly as for example apodemes. Fig. 5. Examples of variability in size and form of leg IV of a male Tarsonemus nodosus Schaarschmidt. All drawings are made in the scale of magnification